In the illumination of work environments, e.g. office lighting, the visual quality of the lighting installation is an important factor in the perception of the lighting. This applies to both recessed and surface mounted lighting installations. The shape of the luminaires in such installations is an important design parameter to achieve the desired appearance of the lighting installation. A luminaire having a high degree of flatness and side wall linearity for instance facilitates the avoidance of unnecessary gaps between luminaires and other elements of the lighting installation, e.g. floor or ceiling tiles of for instance a concealed profile (CP) or plaster ceiling (PC) installation. Where such a luminaire is integrated in a surface mounted installation, the luminaire should have a gap to the ceiling that is as uniform as possible in order to achieve a good linearity perception. Flatness and side wall linearity of luminaires also help to more effectively provide the mechanical and electrical infrastructure of such lighting installations. In addition, front surface smoothness of the luminaire is also advantageous in order to give the lighting installation its desired look and feel.
It is not straightforward to provide a luminaire having the desired flatness and side wall linearity in a cost-effective manner. The manufacturing of such luminaires is typically quite complex using many components and therefore expensive and not environmentally friendly. This can prohibit large-scale adoption of such lighting installation, at least for economic reasons.
U.S. Pat. No. 9,052,075 B2 discloses a troffer fixture for solid state lighting sources. The fixture comprises a door frame assembly that is attached to the pan. The pan housing is defined by a base and two angled side walls. End caps are attached to the side walls. End reflectors extend at an angle away from the end caps and attach to the base. The end caps, the end reflectors, and the base define compartments at both ends of the housing in which components can be housed. A light board is attached to the base using alignment holes in the base and cut-out portions of the end reflectors. The end reflectors retain elements within the compartments, provide added structural stability to the pan, aid in aligning a light board, and reflect light that impinges on them toward the open end of the fixture.